Developments in Glass Technology

Building Design & Construction, 03-04, includes a number of articles on new developments in glass technology.

Testing curtainwall glazing in situ
Keeping Glazed Walls Healthy discusses techniques for in-place verification of the condition of curtainwall glazing units. The article notes that glass units frequently do not last the life of other major curtainwall components, and their evaluation can be important as the building ages, or as part of due-diligance evaluation during building sales.

Test ASTM E576 "Standard Test Method for Frost Point of Sealed Insulating Glass Units in Vertical Position" specifies a method for determining the moisture content of air within sealed glass units and can be used to predict future fogging of units due to internal moisture condensation.

A second ASTM test, identified in the article as E1392, is described as a relatively new and not well known test for non-destructive testing of structural-glazed installations. In these installations glazing is attached to the curtainwall system only with silicone adhesive and without any mechanical attachment. It appears to this author that the ASTM reference provided in the article is incorrect--and should be ASTM C1394 "Standard Guide for In-Situ Structural Silicone Glazing Evaluation".

On a separate topic, the article also discusses the occasional spontaneous breakage of fully tempered glass due to the unpredictable pressence of nickle sulfide inclusions in these glass products. To avoid risks to occupants, some glass manufacturers recommend against the use of fully tempered glass in vertical curtainwall glazing or in other locations where falling glass could pose a threat to building occupants or passers-by.

New Low-E High-Transparency Coating
Pyrolytic glass coating debuts discusses Pilkington's new Eclipse Advantage coating that provides higher transparency and lower reflectivance than Pilkington's current Eclipse product that it replaces. The low-e coating is also noteworthy for being applied in a pyrolytic "hard coat" process that is more durable than competing sputter applied "soft coat" products. The hard coat product is claimed to be less subject to damage during secondary operations such as laminating, cutting, heat treatment, etc.

Product Updates
Products Glass provides several pages of annoucments on glass products related to sound control, fire control, low-e glass, high-efficiency clear glass, protective glass films, safety glass, wire glass, and more.